1. Field of the Invention
The invention relates to a power source system for a vehicle, a vehicle, and a vehicle control method.
2. Description of Related Art
Japanese Patent Application Publication No. 2010-206885 (JP 2010-206885 A) discloses a charging control device for a vehicle that can charge a low-voltage battery, which supplies power to onboard electric components, from a high-voltage battery which is a power source of the vehicle. In such a charging control device, where the voltage of the low-voltage battery is equal to or lower than a predetermined threshold in a power feed mode in which the vehicle does not run, the low-voltage battery is charged using the power stored in the high-voltage battery.
In the charging control device, where the state of charge (SOC) of the high-voltage battery is equal to or less than a lower limit value, the low-voltage battery is not charged from the high-voltage battery. The lower limit value of the SOC of the high-voltage battery is set to a level of the SOC which is minimum necessary to start the engine in the case of a hybrid vehicle (HV) in which the high-voltage battery can be charged by a generator driven by an engine (see JP 2010-206885 A).